According to Aljazeera's correspondent, the 15 were injured after occupation forces fired teargas and rubber bullets at them in the village of Baddu.
Three Palestinians were also arrested. Two Israeli soldiers were wounded by stone throwers.
Troops cut down dozens of olive trees to clear land for the separation barrier, sparking the clashes.
"My olives, my olives," yelled one elderly Palestinian farmer as he threw rocks at construction workers sawing away at his olive trees.
Israel says it is building the barrier for "security" reasons. The Palestinians have denounced the barrier as a land grab. It has disrupted the lives of thousands who have difficulty reaching farms, schools and jobs.
In recent weeks, dozens of anti-barrier protests have erupted in Palestinian villages in the West Bank, particularly those near Jerusalem.
Last month, three Palestinians were killed by Israeli occupation troop fire in such protests.
An elderly Palestinian shouted:
'My olives, my olives'
In Nablus, Israeli troops shot and wounded two Palestinians during an invasion into the West Bank city, our correspondent said. Three other Palestinians were injured when troops fired at stone throwers with rubber bullets, witnesses said.
Meanwhile, scores of Palestinian women protested on Wednesday against what they called US "war crimes" in Iraq.
More than 150 women assembled outside the offices of the United Nations in Gaza where they burned an American flag to protest against US action against Iraqis in several towns and cities over the past few days which has left more than 200 Iraqis dead.
They also handed over a letter addressed to UN Secretary-General Kofi Annan in which they denounced "the grave violations perpetrated against the Iraqi people" by the US forces.
Palestinian women call for an end
to the occupation's 'war crimes'
"We call on you to act to put an end to these violations and war crimes carried out against civilians," the letter added.
In a statement issued in Gaza, Islamic Jihad also condemned the "crimes and atrocious massacres by the American occupation forces against innocent Iraqi civilians".
"The movement blesses the intifada (uprising) of the Iraqi people and the resistance in Falluja and in all the other Iraqi towns," it added, referring to the flashpoint town west of Baghdad where four security workers were brutally killed by Iraqi fighters last week.
"Arab and Muslim people support the Iraqi and Palestinian people for their popular actions against American and Zionist terrorism," the statement continued.
"The massacres committed in Iraq show that America has not come to install peace and democracy but to spread its hegemony, to loot and to colonise."
The Hamas movement also condemned in a statement the "arbitrary killings" carried out by Americans against "our Iraqi brothers".
It also called on Arab countries and Muslims to "protect the Iraqi people, and put an end to the aggressions".